@article{MM2_1985__53_155097,
     author = {Sakari Toppila},
     title = {On the {Spherical} {Derivative} of an {Entire} {Function.}},
     journal = {Manuscripta mathematica},
     pages = {225--234},
     publisher = {mathdoc},
     volume = {53},
     year = {1985},
     zbl = {0595.30040},
     url = {http://geodesic.mathdoc.fr/item/MM2_1985__53_155097/}
}